Steps
In a small bowl, whisk together olive oil, lemon juice, oregano, garlic powder, salt, and pepper.
Place the chicken breast in a shallow dish and pour the marinade over it. Cover and refrigerate for at least 30 minutes.
Preheat the grill to medium-high heat.
Remove the chicken from the marinade and discard the leftover marinade.
Grill the chicken for 6-7 minutes on each side or until fully cooked and juices run clear.
Remove from the grill and let it rest for a few minutes before slicing.
Garnish with lemon slices and serve.